Bangkok United's dream of claiming their first ever Thai League 1 crown suffered a setback when they were held 2-2 by Port on Sunday night.
Before the kick-off, the Angels needed a win over Port to close the gap on leaders Buriram United to two points with a game in hand.
Bangkok United started well at their home ground and went ahead in the 17th minute with Bassel Jradi setting up Mahmoud Eid for a header.
Shortly after Port goalkeeper Somporn Yos had denied Jradi, the visitors equalised through Felipe Amorim on 34 minutes before the Brazilian added the second only two minutes later.
In the second half, Bangkok United controlled most of the game and were able to level the score near the hour mark when Jradi grabbed the equaliser.
The draw has left the Angels three points adrift of the Thunder Castle.
After the match, Bangkok United coach Totchtawan Sripan said: "It was a good match from both teams. Port played well after we scored the first goal, and we conceded two goals in a space of three minutes.
"In the second half, we controlled the game and created many opportunities but were able to convert only one of them.
"I think we can still do it and overtake Buriram. We have a game in hand."
Also on Sunday night, Chonburi's inconsistent form continued after they suffered a 1-0 home defeat at the hands of Ratchaburi. The winning goal came in the first ten minutes of the match with Mateus Lima finding the net.
Hosts Sukhothai recovered from one goal down to claim points following a 3-1 victory over Nakhon Pathom United.
Taku Ito converted a 13th-minute penalty to give the visitors the lead but Lursan Thiamrat (64) and John Baggio (76) turned the tide and Nelson Bonilla made no mistake from the spot in the final stoppage time.
Lamphun Warriors could only pick up a point on their home ground after they were held to a 1-1 draw by bottom-placed Police Tero.